Mustang runs Bad in Rain, Anyone else?
 

Hello,

For some reason when it rains alot and I drive around in my 90 gt runs very poorly. It idles very shaky and seems like it wants to turn off or will not stay on unless I give it alot of gas. Its so bad that I don't drive it when it rains. This is a big pain considering its my daily driver. Could my fender well mounted K&N be getting wet and causing this? Does this happen to anyone else? How can I fix this.

Thanks

I know what you mean. Its hard to drive my mustang in the rain also. Whenever I get right into it my back tires seem to spin a lot. :D No seriously, If your having trouble in the rain I would first replace the cap and rotor. After that I would check your plug wires. More then likely its a problem with wiring of some sort. If you replaced that and still having trouble, check your ignition. If not that then start checking your wiring harnesses going to sensors. But the plug wires, cap and rotor would be my first.

As jruppert said, check the cap and wires. The cap will get light film of dirt, and this seems to collect moisture, causing arcing, thus a misfire.

When plug wires get some age on them, the insulation absorbs moisture, again causing a misfire.

Dirt on the porcelain of the plugs get dirty and allows an arc, thus a misfire, especially when wet weather occurs.

I am not experiencing any misfiring. The problem is more of a stalling out problem. Trying to keep the car on is difficult and a big loss in power. Could the moist weathercap and wires cause this also. The ignition coil is new so I don't think that could be the problem.

Yea, lotta rain in s.a lol, my car has the fender mount filter too, im thinking the same, the power loss could be coming from the humid air? notice dry cool air always makes your car feel snappy:) other than that i dont know, i do try and avoid huge puddles since i dont want to intake water, that would make it stall im sure, also very bad for internals:(

I agree that it sounds electrical. could even have a cracked plug. just do a tune up, plugs, wires, cap, rotor, and take it from there.

had the same thing happen on 2 of my stangs and 4 of my buddies. all of them ended up being bad mass air sensors. they had a little bit different symptoms between them but for the most part they were the same